THE ELECTRODE POTENTIAL OF IRON IN RELATION TO HYDROGEN ION CONCENTRATION

1936 ◽  
Vol 14b (1) ◽  
pp. 31-40 ◽  
Author(s):  
J. W. Shipley ◽  
J. H. Shipley
Keyword(s):  
Electrode Potential ◽  
Chloride Ion ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Iron Electrode ◽  
General Corrosion ◽  
Citrate Buffer ◽  
Hydrogen Ion Concentration ◽  
Electrically Conducting ◽  
Ph Values

The electrode potential of iron immersed in phosphate, borate and citrate buffers of varying hydrogen ion concentration was measured, using a normal calomel electrode as the second half of the cell. Breaks in the potential of the iron electrode amounting to as much as 0.7 volts were found to occur at definite pH values for each series of buffers. The electrode exhibited an "initial" and "final" potential depending on the pH of the electrolyte and the time of immersion, the "final" value requiring several days to become established. The "final" break in the electrode potential of 0.74 volts in the pure phosphate buffer occurred between a pH of 3.1 and 4.0, that in the pure borate buffer, of 0.75 volts, occurred between a pH of 4.3 and 4.6, and in the pure citrate buffer, of 0.77 volts, between a pH of 10.1 and 10.9. The effect of chloride ion and de-aeration on the electrode potential was observed. It is suggested that the potential of the iron electrode is determined by the presence or absence of a non electrically conducting film or deposit on the iron, the formation of which is a function of the nature of the electrolyte and its hydrogen ion concentration. De-aeration apparently had no effect on the electrode potential, but the presence of chloride ion affected the establishing of the "final" potential and caused the break in voltage to appear irregularly at a much lower hydrogen ion concentration.At pH values below that at which the break in potential occurred, corrosion of the iron electrode was marked, and the electrode potential remained high, while, at pH values above the break, corrosion was virtually inhibited or confined to local spots on the electrode, and the electrode potential remained low. The presence of the chloride ion stimulated local corrosion and permitted general corrosion to proceed at a lower hydrogen ion concentration.

scholarly journals The Hydrogen Ion Concentration of the Cells of some Marine Algæ

1922 ◽  
Vol 12 (4) ◽  
pp. 785-788 ◽  
Author(s):  
W. R. G. Atkins
Keyword(s):  
Marine Algae ◽  
Plant Cells ◽  
Hydrogen Ion ◽  
Land Plants ◽  
Ion Concentration ◽  
Hydrogen Ion Concentration ◽  
Ph Values ◽  
Optimum Ph ◽  
Acid Character

The measurements recorded for marine algæ of various groups show that the reaction of the sap is in most cases almost neutral, and in no case is the sap of the pronounced acid character met with in many land plants. This being so it follows that the enzymes concerned in the metabolism of these algæ must be quite different from those which effect corresponding changes in land plants, as may be seen on referring to the optimum pH values for various enzymes quoted in the writer's previous paper on the reaction of plant cells (1922).

scholarly journals THE EFFECT OF HYDROGEN ION CONCENTRATION ON SWELLING OF CELLS

1926 ◽  
Vol 9 (5) ◽  
pp. 709-714 ◽  
Author(s):  
Baldwin Lucke ◽  
Morton McCutcheon
Keyword(s):  
Hydrogen Ion ◽  
Ion Concentration ◽  
Hydrogen Ion Concentration ◽  
Ph Values ◽  
Wide Range

1. The effect of HCl, NaOH, CO2, and NH3 on the volume of unfertilized Arbacia eggs was tested over a wide range of pH values. 2. No swelling occurred, except in HCl solutions, and there not until after injury or death had occurred. 3. Whereas the volume of erythrocytes and of proteins such as gelatin is known to be dependent on the pH of the solution, such a relation does not exist in the case of living and uninjured cells, at least of the type tested.

scholarly journals Chemical characteristics of precipitation and hydrogen input in throughfall and stemflow under some eastern Canadian forest stands

1983 ◽  
Vol 13 (5) ◽  
pp. 948-955 ◽  
Author(s):  
M. K. Mahendrappa
Keyword(s):  
Weighted Average ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Chemical Characteristics ◽  
Weighted Mean ◽  
Hydrogen Ion Concentration ◽  
Average Value ◽  
Ph Values ◽  
Nitrate N ◽  
Forest Experiment Station

At the Acadia Forest Experiment Station (AFES) in central New Brunswick chemical characteristics of rain samples collected at five different locations were determined during the 1977–1981 period. Throughfall and stemflow samples from six softwood and three hardwood stands were collected and chemically characterized starting from the early 70's. In 1976 two of four plots in each of the stands were treated with urea at a rate of 225 kg N•ha−1. Both the quantities of rain and their pH values varied considerably between collections, months, and years. The weighted mean pH of summer (May–October) rain collected intensively during the 1977–1981 period ranged from 4.5 to 5.1, with an overall weighted average value of 4.75 for the 5 years. Sulfur and nitrate N measured during May–October 1982 amounted to 6.18 and 1.52 kg•ha−1, respectively, for the 6-month period. The concentration of hydrogen ion in the throughfall was less than that in the rain. Hardwood throughfall had lower hydrogen levels (higher pH) than the softwood throughfall. The pH of the stemflow from softwoods was lower than that of rain in most cases. Although not significantly, the hydrogen ion concentration of both throughfall and stemflow on the fertilized plots was lower than on the untreated plots. The hydrogen load of rain was reduced by all tree species, but there was considerable variation between species in their abilities to decrease total hydrogen reaching the soil.

THE MECHANISM OF THE ALCOHOLYSIS OF ALIPHATIC NITRITES: II. ACID-CATALYZED ALCOHOLYSIS OF 1-METHYLHEPTYL NITRITE

1961 ◽  
Vol 39 (4) ◽  
pp. 947-953 ◽  
Author(s):  
A. D. Allen ◽  
G. R. Schonbaum
Keyword(s):  
Reaction Rate ◽  
Chloride Ion ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Lithium Salts ◽  
Hydrogen Ion Concentration ◽  
First Order ◽  
Low Concentrations ◽  
Acid Catalyzed ◽  
Asymmetric Carbon

The acid-catalyzed alcoholysis of 1-methylheptyl nitrite has been studied kinetically. The reaction rate is first order with respect to both the nitrite and the hydrogen ion concentration, and the reaction does not involve the asymmetric carbon center. Addition of lithium salts (chloride and perchlorate) indicates catalysis by chloride ion. Addition of water in low concentrations inhibits the reaction strongly. These results and the mechanism of the reactions are discussed in terms of the properties of the alcohols and the dissociation of the acid catalysts in the alcohols used.

The Relation between the Rate of Production of Gastric Juice and its Electrolyte Concentrations

1970 ◽  
Vol 39 (1) ◽  
pp. 61-75 ◽  
Author(s):  
M. Hobsley ◽  
W. Silen
Keyword(s):  
Linear Relationship ◽  
Gastric Juice ◽  
Chloride Ion ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Hydrogen Ion Concentration ◽  
Acid Component ◽  
Volume Rate ◽  
Fixed Composition ◽  
Analytical Errors

1. Repeated 15-min collections of gastric juice were made during the plateau of response to an intravenous infusion of histamine diphosphate 0·01 mg h−1 kg−1 and the samples measured and their electrolyte concentrations estimated. A linear relationship was found between chloride output and the volume-rate of overall secretion and between hydrogen ion output and the same rate of secretion, while a multivariate linear relationship was also found between all three variables. 2. A mathematical analysis of these results suggests that if gastric secretion consists of an acid and a non-acid component, each of fixed composition, then the acid component has the composition H = 143 mEq/l, K = 16 mEq/l, Cl = 169 mEq/l, and the non-acid component is secreted at the same rate in different subjects under these circumstances. 3. The data enable gross sampling and analytical errors to be detected; in particular, the volume-rate of secretion can be predicted from hydrogen ion concentration, better from chloride ion concentration, and best from the concentrations of both ions. 4. For single samples such predictions appear to be superior to the direct measurement of volume.

scholarly journals INFLUENCE OF TEMPERATURE AND HYDROGEN ION CONCENTRATION UPON THE SPORE CYCLE OF BACILLUS SUBTILIS

1919 ◽  
Vol 1 (4) ◽  
pp. 421-428 ◽  
Author(s):  
Arao Itano ◽  
James Neill
Keyword(s):  
Ph Value ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Practical Application ◽  
Vegetative Cells ◽  
Hydrogen Ion Concentration ◽  
Influence Of Temperature ◽  
Ph Values ◽  
Metabolic Products ◽  
Slight Growth

1. At 5°C. no germination took place. 2. At 25°C. and at 37°C. germination occurs if the hydrogen ion concentration of the broth is kept between pH 5 and pH 10, but not at higher or lower pH values. 3. The completion of the spore cycle likewise requires a hydrogen ion concentration between pH 5 and pH 10. 4. The spores can germinate when the pH value is 10, although after germination the vegetative cells multiply only to a very slight extent and soon pass into spores. 5. The slight growth and multiplication of vegetative cells in broth of pH 10 suggest that the formation of endospores in this medium must be caused largely by the unfavorable reaction of the medium rather than by the accumulation of metabolic products. 6. Automatic adjustment of the medium seems to play a rôle in the completion of the spore cycle. 7. The results are not only of theoretical importance but they have a practical application to the preservation of food by canning and by other methods.

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